The present invention relates to an implantable lubrication device for lubricating a joint of a human or mammal patient, an implantable lubrication system and methods of treating a human or mammal patient by means of said implantable lubrication system.
The present invention is particularly suitable for long term or permanent introduction of lubricating fluid in a joint, i.e. for introduction of lubricating fluid on a permanent or periodical basis over long time intervals, e.g. over years.
The lubricating fluid (synovial fluid) reduces friction between the articular cartilage and other tissues in a joint and lubricates and cushions the bone and tissue components of the joint during movement. If the lubricating fluid is negatively affected and/or the joint articular cartilage usually covering the joint bone is damaged, in most cases due to older age and/or continuing extensive or abnormal strain on human or mammal joints (e.g. knee joint, hip joint), this can result in a degenerative joint disease (also known as osteoarthritis) characterized by a painful inflammation of the joint. Upon pathological reduction and change of composition of the lubricating fluid within the joint space, which consists of the articulating surfaces of the adjacent bones with the joint being stabilized and encompassed by the joint capsule and the synovial membrane, the lubricating fluid can no longer perform its usual task, i.e. lubrication of joint areas and shock absorption, together with the articular cartilage.
If the articular cartilage is also severely damaged due to osteoarthritis or the like and/or the synovial fluid is reduced or altered in its composition reducing its potential to lower friction within the joint, the articulating surfaces are subjected to high friction and increased wear causing a painful inflammation of the joint. This can result in serious restraints of movement, especially in walking and standing, which further augment degenerative processes of the joint. Degenerative joint disease is highly prevalent in the western world, with this disease being one of the leading causes for chronic disability in Europe and the US.
Patients with osteoarthritis require a regular long term treatment by which lubricating fluid is introduced into the affected joint, which, on the one hand, restores the physiological functionality of the damaged joint as far as possible and, on the other hand, involves as little extra stress as possible—both physical and psychological—for the patient.
A known standard therapy is periodical extracorporeal injection of synthetic lubricating fluid into the joint space by a syringe in order to substitute the absent physiological lubricating fluid. In such conventional treatment it is inconvenient for the patient to deliver the lubricating fluid at regular time intervals through the skin and the joint capsule into the joint by way of a syringe. Also, this may cause injuries to the skin and the joint capsule, which increases the risk of severe infections of the delicate joint tissues. Therefore, an injection may not be performed more often than every half a year.
However, many patients need a replenishment of lubricating fluid more often, i.e. a continuous replenishment of small amounts of lubricating fluid.